3.1.1.1 Natural hazards -> 3.1.1.2 Tectonic hazards

[3.1.1.1] what is the definition of a 'natural hazard' ?

A potentially dangerous physical event occurring close to a population ( who are said to be a risk )

[3.1.1.1] What are the four types of natural hazards?

tectonic, atmospheric, geomorphological, biological

[3.1.1.1] Which natural hazards are tectonic?

Earthquake, Volcanic Eruption, Landslide, Tsunami

[3.1.1.1] Which natural hazards are Geomorphological?

Floods, Landslides

[3.1.1.1] Which natural hazards are Atmospheric?

Tropical storms, Droughts, Tornadoes

[3.1.1.1] Which natural hazards are Biological?

Pests, Disease

[3.1.1.1] What is the definition of a 'Hazard Risk' ?

Hazard Risk is the chance that an area or population will be affected by a natural hazard.

[3.1.1.1] What are the 5 factors to consider when understanding the risk of a hazard?

Natural Factors, Magnitude/Size of event, Frequency/Time of day, Population Density, Level of Development.

[3.1.1.1] 5 factors to consider when understanding the risk of a hazard: What is an example of Natural factors?

Coastal areas are more vulnerable to tsunamis.

Soil composition can influence the intensity of shaking during an earthquake.

[3.1.1.1] 5 factors to consider when understanding the risk of a hazard: What is an example of Magnitude/Size of Event?

If the magnitude of an event is higher, it means it will cause more damage.

[3.1.1.1] 5 factors to consider when understanding the risk of a hazard: What is an example of Frequency/Time of Day?

Frequent earthquakes can overwhelm a region's economic and material resources, stopping its ability to fully restore protective infrastructure before another disaster happens.

A natural hazard happening during the daytime is likely to cause more fatalities due to higher concentrations of people outside.

[3.1.1.1] 5 factors to consider when understanding the risk of a hazard: What is an example of Population Density?

As the global population increases, more people inhabit areas susceptible to natural disasters, thereby raising the overall risk.

[3.1.1.1] 5 factors to consider when understanding the risk of a hazard: What is an example of Level of Development?

HICs have the wealth to invest in infrastructure, preparedness, and long-term recovery efforts, whereas LICs often lack the financial resources to do so. Therefore, LICs are more susceptible to disasters.

[3.1.1.1] earthquakes are measured in terms of their _________

magnitude

[3.1.1.1] magnitude is a measure of ...

the amount of ground movement and the amount of energy released during an earthquake event.

[3.1.1.1] magnitude is measured on the ...

moment magnitude scale (Mw)

[3.1.1.1] for each step on the moment magnitude scale, the ground movement is how many times greater than the one before?

10

[3.1.1.1] volcanic eruptions are measured by using the ....

volcanic explosivity index (VEI)

[3.1.1.1] VEI is a measure of ....

how much lava and ash (tephra) is released and how high into the atmosphere it is ejected

[3.1.1.1] each step of the VEI is how many times more powerful than the one before?

10

[3.1.1.1] Tropical storms are measured using the ...

saffir-simpson wind scale

[3.1.1.1] the saffir-simpson wind scale is a measure of...

the intensity of a tropical storm based on its sustained wind speed.

[3.1.1.1] each step of the saffir-simpson scale is how many times more damaging than the step before?

four

[3.1.1.2] what are the four layers of the earth?

inner core, outer core, mantle, crust

[3.1.1.2] what are the two types of crust?

oceanic crust and continental crust

[3.1.1.2] what is plate tectonics theory?

the current theory is called slab pull theory which suggests that the movement is the result of the weight of the denser oceanic plates subducting and dragging the rest of the plate along.

[3.1.1.2] which plate boundaries do earthquakes occur in and where do earthquakes occur the most?

earthquakes occur at all types of plate boundaries and most earthquakes occur along the pacific " ring of fire " (approx 90%)

[3.1.1.2] which plate boundaries do volcanoes occur in and where do volcanoes occur the most?

most volcanoes occur at constructive and destructive plate boundaries and the majority of active volcanoes (approx 75%) are located around the rim of the pacific ocean called the "ring of fire".

[3.1.1.2] what are the 3 types of plate boundaries?

constructive, destructive, conservative

[3.1.1.2] how do constructive plate boundaries work?

At a constructive plate boundary, the plates are moving apart. As they move apart, magma rises to fill the gap. This leads to the formation of volcanoes and eruptions.

[3.1.1.2] what is an irl example of a constructive plate boundary?

The Mid Atlantic Ridge

[3.1.1.2] which natural hazards occur at constructive plate boundaries?

volcanic eruptions and earthquakes

[3.1.1.2] how do destructive plate boundaries work?

At a destructive plate boundary, the plates are moving together. The denser, heavier oceanic plate subducts under the lighter, less dense continental plate. This leads to friction and heat, which melts the crust and forms magma. Magma rises to the surface through cracks in the crust. It erupts of the surface as lava and forms a volcano.

[3.1.1.2] what is an irl example of a destructive plate boundary?

The boundary between the Nazca plate and the South American plate.

[3.1.1.2] which natural hazards occur at destructive plate boundaries?

volcanic eruptions and earthquakes.

[3.1.1.2] how do conservative plate boundaries work?

At a conservative plate boundary, the plates move past each other in opposite directions OR in the same direction at different speeds.

[3.1.1.2] what is an irl example of a conservative plate boundary?

San Andreas Fault

[3.1.1.2] which natural hazards occur at conservative plate boundaries?

only earthquakes

[3.1.1.2] what is the date, event, magnitude, location, and duration of the 2010 Chile earthquake?

USE THIS TEMPLATE WHEN TYPING:

date:

event:

magnitude:

location:

duration:

date: 27th February 2010

event: huge earthquake

magnitude: 8.8 on richter scale

location: off the coast of chile

duration: over three minutes

[3.1.1.2] what is the date, event, magnitude, location, and duration of the 2015 Nepal earthquake?

USE THIS TEMPLATE WHEN TYPING:

date:

event:

magnitude:

location:

duration:

date: 25th april 2015

event: earthquake

magnitude: 7.9

location: near the capital city of kathmandu, in central Nepal.

duration: 50-55 seconds

[3.1.1.2] what are the primary effects of the 2010 Chile earthquake? (4)

- around 500 killed and 12,000 injured. 800,000 affected overall.

- Much of Chile lost power, water supplies and communications.

- Estimated cost of USD $30 billion.

- 22,000 homes, 4,500 schools, 53 ports and 56 schools damaged.

[3.1.1.2] what are the secondary effects of the 2010 Chile earthquakes? (3)

- Landslides triggered by the earthquake damaged 1500 km of roads. Debris blocked roads for weeks, which slowed relief efforts.

- Fires broke out in buildings due to burst pipes

- A tsunami was triggered by the earthquake, which devastated coastal towns.

[3.1.1.2] what are the primary effects of the 2015 Nepal earthquake? (4)

- 9,000 people killed and 20,000 injured. 8 million affected overall.

- electricity, water supplies, and communications affected.

- estimated cost of over $5 billion

- 7,000 schools destroyed and hospitals overwhelmed.

[3.1.1.2] what are the secondary effects of the 2015 Nepal earthquakes? (4)

- ground shaking triggered landslides and avalanches blocking roads.

- avalanches on mount everest killed at least 19 people.

- a landslide blocked the Kali Gandaki River.

- An avalanche in the Langtang region left 250 people missing.

[3.1.1.2] what were the immediate responses to the Chile 2010 earthquake? (5)

- emergency services were deployed quickly

- emergency field hospitals were set up to help the injured.

- within 24 hours, temporary repairs were made to the route 5 highway. this allowed the response teams to move to remote communities.

- power and water was restored to 90% of homes within 10 days

- temporary shelters were set up for the homeless.

[3.1.1.2] what were the immediate responses to the Nepal 2015 earthquake? (4)

- international aid quickly arrived from the UK, India and China. They brought search and rescue teams, medical support and essential supplies.

- helicopters were used for search, rescue and supply distribution.

- Half a million tents were provided after the earthquake, many from UNICEF.

- 300,000 people fled from the capital to seek shelter elsewhere.

[3.1.1.2] what were the long term responses to the Chile 2010 earthquake? (4)

- Chile set up a national housing reconstruction plan one month after the earthquake,

- Thousands of houses and buildings were deemed unsafe to stay standing, and had to be demolished.

- Foreign aid was not heavily relied upon as Chile had the funds available for reconstruction and recovery.

- The president of Chile announced that full recovery could take 4 years.

[3.1.1.2] what were the long term responses to the Nepal 2015 earthquake? (6)

- Three-quarters of homes that were destroyed from the earthquake were either fully rebuilt or under repair by 2019.

- The government introduced stricter building codes with better earthquake resistance.

- Landslides were cleared and roads were repaired.

- In June 2015, Nepal hosted an international conference to seek advice and financial support from other countries to help the recovery process.

- By August 2015, repairs to Everest base camp and mountain routes meant the area could be reopened to mountaineers.

- In September 2015, Nepal suffered severe shortages of fuel, medicines and earthquake relief materials after India imposed a blockade at the Nepal-India border, stopping goods from entering Nepal.